Many electrical devices are used in applications where it may be desirable to restrict access to their use, for example, where such use may be dangerous when involving unqualified individuals or where an electrical device is not functioning properly. While access to some electrical devices may be restricted by electronic safeguards, such as, for example, by electronic passcodes or key cards, a simpler arrangement for preventing use of an electrical device may involve use of a power connection lockout device, in which an enclosure or other obstruction is lockably secured to a power connection by which the electrical device is powered, thereby preventing electrical connection of the electrical device to a power source, such as a corresponding socket or other such connector.